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A153407
Middle of 3 consecutive prime numbers such that p1*p2*p3+d1+d2+1=average of twin prime pairs, d1(delta)=p2-p1,d2(delta)=p3-p2.
7
4817, 9011, 13841, 33797, 35027, 48341, 51581, 52163, 61331, 62213, 77747, 95111, 102611, 105143, 105683, 109673, 111773, 114797, 119759, 128237, 135389, 136733, 138683, 149213, 153953, 159791, 163211, 165443, 174851, 188681, 195977, 208037
OFFSET
1,1
COMMENTS
4813*4817*4831+4+14=112002971670+-1=primes,...
LINKS
MATHEMATICA
lst={}; Do[p1=Prime[n]; p2=Prime[n+1]; p3=Prime[n+2]; d1=p2-p1; d2=p3-p2; a=p1*p2*p3+d1+d2+1; If[PrimeQ[a-1]&&PrimeQ[a+1], AppendTo[lst, p2]], {n, 8!}]; lst
cnpQ[{a_, b_, c_}]:=Module[{p=a*b*c+(b-a)+(c-b)+1}, And@@PrimeQ[p+{1, -1}]]; Transpose[Select[Partition[Prime[Range[20000]], 3, 1], cpnQ]][[2]] (* Harvey P. Dale, Jul 30 2013 *)
KEYWORD
nonn
AUTHOR
STATUS
approved